setting field from SelectOneMenu; JSF 1.2

Question

I have a problem related to setting property by selecting idem in SelectOneMenu. This is it: in presentation layer I have:

<h:selectOneMenu id="fio" value="#{page.personOwner}" disabled="#{page.readonly}" readonly="#{page.readonly}" >         
                                <a4j:support event="onchange" reRender="generalForm" ajaxSingle="true" />           
                                <f:selectItems value="#{page.agrGrpRelInsPersons}" ></f:selectItems>
                            </h:selectOneMenu>

so, I can fill menu with 'agrGrpRelInsPersons' which is List. This is the metod which returns it:

public List<SelectItem> getAgrGrpRelInsPersons(){
        List<SelectItem> persons = new ArrayList<SelectItem>();
        for(AgrGrpRel agrGrpRel : getAgreement().getAgrGrpRels()){
            for(InoPerRel inoPerRel :agrGrpRel.getAgreement().getInsObject().getInoPerRels()){
                persons.add(new SelectItem(((Person)inoPerRel.getPerson()), inoPerRel.getPerson().getName1()+" "+inoPerRel.getPerson().getName2()+" "+inoPerRel.getPerson().getName3()));
                }
            }
        return persons;
    }

..here you can see that as first parameter in new SelectItem Im passing an object Person, which I want to be set to setter:

public void setPersonOwner(Person person){
        getAgreementExt().setOwner(person);
    }

However, this is not working for me.. Now I would be happy to know what Im doing wrong or what am I missing.

Thanks for your suggestions!